--- /dev/null
+/*
+ * Copyright (c) 2007 Apple Inc. All Rights Reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_LICENSE_HEADER_END@
+ */
+
+/***********************************************************************
+* objc-os.m
+* OS portability layer.
+**********************************************************************/
+
+#define OLD 1
+#include "objc-os.h"
+#include "objc-private.h"
+#include "objc-loadmethod.h"
+
+#if TARGET_OS_WIN32
+
+#include "objcrt.h"
+
+malloc_zone_t *_objc_internal_zone(void)
+{
+ return NULL;
+}
+
+int monitor_init(monitor_t *c)
+{
+ // fixme error checking
+ HANDLE mutex = CreateMutex(NULL, TRUE, NULL);
+ while (!c->mutex) {
+ // fixme memory barrier here?
+ if (0 == InterlockedCompareExchangePointer(&c->mutex, mutex, 0)) {
+ // we win - finish construction
+ c->waiters = CreateSemaphore(NULL, 0, 0x7fffffff, NULL);
+ c->waitersDone = CreateEvent(NULL, FALSE, FALSE, NULL);
+ InitializeCriticalSection(&c->waitCountLock);
+ c->waitCount = 0;
+ c->didBroadcast = 0;
+ ReleaseMutex(c->mutex);
+ return 0;
+ }
+ }
+
+ // someone else allocated the mutex and constructed the monitor
+ ReleaseMutex(mutex);
+ CloseHandle(mutex);
+ return 0;
+}
+
+void mutex_init(mutex_t *m)
+{
+ while (!m->lock) {
+ CRITICAL_SECTION *newlock = malloc(sizeof(CRITICAL_SECTION));
+ InitializeCriticalSection(newlock);
+ // fixme memory barrier here?
+ if (0 == InterlockedCompareExchangePointer(&m->lock, newlock, 0)) {
+ return;
+ }
+ // someone else installed their lock first
+ DeleteCriticalSection(newlock);
+ free(newlock);
+ }
+}
+
+
+void recursive_mutex_init(recursive_mutex_t *m)
+{
+ // fixme error checking
+ HANDLE newmutex = CreateMutex(NULL, FALSE, NULL);
+ while (!m->mutex) {
+ // fixme memory barrier here?
+ if (0 == InterlockedCompareExchangePointer(&m->mutex, newmutex, 0)) {
+ // we win
+ return;
+ }
+ }
+
+ // someone else installed their lock first
+ CloseHandle(newmutex);
+}
+
+
+WINBOOL APIENTRY DllMain( HMODULE hModule,
+ DWORD ul_reason_for_call,
+ LPVOID lpReserved
+ )
+{
+ switch (ul_reason_for_call) {
+ case DLL_PROCESS_ATTACH:
+ environ_init();
+ tls_init();
+ lock_init();
+ sel_init(NO);
+ exception_init();
+ break;
+
+ case DLL_THREAD_ATTACH:
+ break;
+
+ case DLL_THREAD_DETACH:
+ case DLL_PROCESS_DETACH:
+ break;
+ }
+ return TRUE;
+}
+
+OBJC_EXPORT void *_objc_init_image(HMODULE image, const objc_sections *sects)
+{
+ header_info *hi = _malloc_internal(sizeof(header_info));
+ size_t count, i;
+
+ hi->mhdr = (const headerType *)image;
+ hi->info = sects->iiStart;
+ hi->allClassesRealized = NO;
+ hi->os.modules = sects->modStart ? (Module *)((void **)sects->modStart+1) : 0;
+ hi->os.moduleCount = (Module *)sects->modEnd - hi->os.modules;
+ hi->os.protocols = sects->protoStart ? (struct old_protocol **)((void **)sects->protoStart+1) : 0;
+ hi->os.protocolCount = (struct old_protocol **)sects->protoEnd - hi->os.protocols;
+ hi->os.imageinfo = NULL;
+ hi->os.imageinfoBytes = 0;
+ // hi->os.imageinfo = sects->iiStart ? (uint8_t *)((void **)sects->iiStart+1) : 0;;
+// hi->os.imageinfoBytes = (uint8_t *)sects->iiEnd - hi->os.imageinfo;
+ hi->os.selrefs = sects->selrefsStart ? (SEL *)((void **)sects->selrefsStart+1) : 0;
+ hi->os.selrefCount = (SEL *)sects->selrefsEnd - hi->os.selrefs;
+ hi->os.clsrefs = sects->clsrefsStart ? (Class *)((void **)sects->clsrefsStart+1) : 0;
+ hi->os.clsrefCount = (Class *)sects->clsrefsEnd - hi->os.clsrefs;
+
+ count = 0;
+ for (i = 0; i < hi->os.moduleCount; i++) {
+ if (hi->os.modules[i]) count++;
+ }
+ hi->mod_count = 0;
+ hi->mod_ptr = 0;
+ if (count > 0) {
+ hi->mod_ptr = malloc(count * sizeof(struct objc_module));
+ for (i = 0; i < hi->os.moduleCount; i++) {
+ if (hi->os.modules[i]) memcpy(&hi->mod_ptr[hi->mod_count++], hi->os.modules[i], sizeof(struct objc_module));
+ }
+ }
+
+ _objc_appendHeader(hi);
+
+ if (PrintImages) {
+ _objc_inform("IMAGES: loading image for %s%s%s\n",
+ _nameForHeader(hi->mhdr),
+ headerIsBundle(hi) ? " (bundle)" : "",
+ _objcHeaderIsReplacement(hi) ? " (replacement)":"");
+ }
+
+ _read_images(&hi, 1);
+
+ return hi;
+}
+
+OBJC_EXPORT void _objc_load_image(HMODULE image, header_info *hinfo)
+{
+ prepare_load_methods(hinfo);
+ call_load_methods();
+}
+
+OBJC_EXPORT void _objc_unload_image(HMODULE image, header_info *hinfo)
+{
+ _objc_fatal("image unload not supported");
+}
+
+
+// TARGET_OS_WIN32
+#elif TARGET_OS_MAC
+
+__private_extern__ void mutex_init(mutex_t *m)
+{
+ pthread_mutex_init(m, NULL);
+}
+
+
+__private_extern__ void recursive_mutex_init(recursive_mutex_t *m)
+{
+ // fixme error checking
+ pthread_mutex_t *newmutex;
+
+ // Build recursive mutex attributes, if needed
+ static pthread_mutexattr_t *attr;
+ if (!attr) {
+ pthread_mutexattr_t *newattr =
+ _malloc_internal(sizeof(pthread_mutexattr_t));
+ pthread_mutexattr_init(newattr);
+ pthread_mutexattr_settype(newattr, PTHREAD_MUTEX_RECURSIVE);
+ while (!attr) {
+ if (OSAtomicCompareAndSwapPtrBarrier(0, newattr, (void**)&attr)) {
+ // we win
+ goto attr_done;
+ }
+ }
+ // someone else built the attr first
+ _free_internal(newattr);
+ }
+ attr_done:
+
+ // Build the mutex itself
+ newmutex = _malloc_internal(sizeof(pthread_mutex_t));
+ pthread_mutex_init(newmutex, attr);
+ while (!m->mutex) {
+ if (OSAtomicCompareAndSwapPtrBarrier(0, newmutex, (void**)&m->mutex)) {
+ // we win
+ return;
+ }
+ }
+
+ // someone else installed their mutex first
+ pthread_mutex_destroy(newmutex);
+}
+
+
+/***********************************************************************
+* bad_magic.
+* Return YES if the header has invalid Mach-o magic.
+**********************************************************************/
+__private_extern__ BOOL bad_magic(const headerType *mhdr)
+{
+ return (mhdr->magic != MH_MAGIC && mhdr->magic != MH_MAGIC_64 &&
+ mhdr->magic != MH_CIGAM && mhdr->magic != MH_CIGAM_64);
+}
+
+
+static const segmentType *
+getsegbynamefromheader(const headerType *head, const char *segname)
+{
+#ifndef __LP64__
+#define SEGMENT_CMD LC_SEGMENT
+#else
+#define SEGMENT_CMD LC_SEGMENT_64
+#endif
+ const segmentType *sgp;
+ unsigned long i;
+
+ sgp = (const segmentType *) (head + 1);
+ for (i = 0; i < head->ncmds; i++){
+ if (sgp->cmd == SEGMENT_CMD) {
+ if (strncmp(sgp->segname, segname, sizeof(sgp->segname)) == 0) {
+ return sgp;
+ }
+ }
+ sgp = (const segmentType *)((char *)sgp + sgp->cmdsize);
+ }
+ return NULL;
+#undef SEGMENT_CMD
+}
+
+
+static header_info * _objc_addHeader(const headerType *mhdr)
+{
+ size_t info_size = 0;
+ const segmentType *objc_segment;
+ const objc_image_info *image_info;
+ const segmentType *data_segment;
+ header_info *result;
+ ptrdiff_t image_slide;
+
+ if (bad_magic(mhdr)) return NULL;
+
+ // Weed out duplicates
+ for (result = FirstHeader; result; result = result->next) {
+ if (mhdr == result->mhdr) return NULL;
+ }
+
+ // Locate the __OBJC segment
+ image_slide = _getImageSlide(mhdr);
+ image_info = _getObjcImageInfo(mhdr, image_slide, &info_size);
+ objc_segment = getsegbynamefromheader(mhdr, SEG_OBJC);
+ data_segment = getsegbynamefromheader(mhdr, SEG_DATA);
+ if (!objc_segment && !image_info) return NULL;
+
+ // Allocate a header_info entry.
+ result = _calloc_internal(sizeof(header_info), 1);
+
+ // Set up the new header_info entry.
+ result->mhdr = mhdr;
+ result->os.image_slide = image_slide;
+ result->os.objcSegmentHeader = objc_segment;
+ result->os.dataSegmentHeader = data_segment;
+#if !__OBJC2__
+ // mhdr and image_slide must already be set
+ result->mod_count = 0;
+ result->mod_ptr = _getObjcModules(result, &result->mod_count);
+#endif
+ result->info = image_info;
+ dladdr(result->mhdr, &result->os.dl_info);
+ result->allClassesRealized = NO;
+
+ // dylibs are not allowed to unload
+ // ...except those with image_info and nothing else (5359412)
+ if (result->mhdr->filetype == MH_DYLIB && _hasObjcContents(result)) {
+ dlopen(result->os.dl_info.dli_fname, RTLD_NOLOAD);
+ }
+
+ // Make sure every copy of objc_image_info in this image is the same.
+ // This means same version and same bitwise contents.
+ if (result->info) {
+ const objc_image_info *start = result->info;
+ const objc_image_info *end =
+ (objc_image_info *)(info_size + (uint8_t *)start);
+ const objc_image_info *info = start;
+ while (info < end) {
+ // version is byte size, except for version 0
+ size_t struct_size = info->version;
+ if (struct_size == 0) struct_size = 2 * sizeof(uint32_t);
+ if (info->version != start->version ||
+ 0 != memcmp(info, start, struct_size))
+ {
+ _objc_inform("'%s' has inconsistently-compiled Objective-C "
+ "code. Please recompile all code in it.",
+ _nameForHeader(mhdr));
+ }
+ info = (objc_image_info *)(struct_size + (uint8_t *)info);
+ }
+ }
+
+ _objc_appendHeader(result);
+
+ return result;
+}
+
+
+#ifndef NO_GC
+
+/***********************************************************************
+* _gcForHInfo.
+**********************************************************************/
+__private_extern__ const char *_gcForHInfo(const header_info *hinfo)
+{
+ if (_objcHeaderRequiresGC(hinfo)) return "requires GC";
+ else if (_objcHeaderSupportsGC(hinfo)) return "supports GC";
+ else return "does not support GC";
+}
+__private_extern__ const char *_gcForHInfo2(const header_info *hinfo)
+{
+ if (_objcHeaderRequiresGC(hinfo)) return " (requires GC)";
+ else if (_objcHeaderSupportsGC(hinfo)) return " (supports GC)";
+ else return "";
+}
+
+
+/***********************************************************************
+* check_gc
+* Check whether the executable supports or requires GC, and make sure
+* all already-loaded libraries support the executable's GC mode.
+* Returns TRUE if the executable wants GC on.
+**********************************************************************/
+static BOOL check_wants_gc(void)
+{
+ const header_info *hi;
+ BOOL appWantsGC;
+
+ // Environment variables can override the following.
+ if (DisableGC) {
+ _objc_inform("GC: forcing GC OFF because OBJC_DISABLE_GC is set");
+ appWantsGC = NO;
+ }
+ else {
+ // Find the executable and check its GC bits.
+ // If the executable cannot be found, default to NO.
+ // (The executable will not be found if the executable contains
+ // no Objective-C code.)
+ appWantsGC = NO;
+ for (hi = FirstHeader; hi != NULL; hi = hi->next) {
+ if (hi->mhdr->filetype == MH_EXECUTE) {
+ appWantsGC = _objcHeaderSupportsGC(hi) ? YES : NO;
+ if (PrintGC) {
+ _objc_inform("GC: executable '%s' %s",
+ _nameForHeader(hi->mhdr), _gcForHInfo(hi));
+ }
+ }
+ }
+ }
+ return appWantsGC;
+}
+
+
+/***********************************************************************
+* verify_gc_readiness
+* if we want gc, verify that every header describes files compiled
+* and presumably ready for gc.
+************************************************************************/
+static void verify_gc_readiness(BOOL wantsGC, header_info **hList,
+ uint32_t hCount)
+{
+ BOOL busted = NO;
+ uint32_t i;
+
+ // Find the libraries and check their GC bits against the app's request
+ for (i = 0; i < hCount; i++) {
+ header_info *hi = hList[i];
+ if (hi->mhdr->filetype == MH_EXECUTE) {
+ continue;
+ }
+ else if (hi->mhdr == &_mh_dylib_header) {
+ // libobjc itself works with anything even though it is not
+ // compiled with -fobjc-gc (fixme should it be?)
+ }
+ else if (wantsGC && ! _objcHeaderSupportsGC(hi)) {
+ // App wants GC but library does not support it - bad
+ _objc_inform_now_and_on_crash
+ ("'%s' was not compiled with -fobjc-gc or -fobjc-gc-only, "
+ "but the application requires GC",
+ _nameForHeader(hi->mhdr));
+ busted = YES;
+ }
+ else if (!wantsGC && _objcHeaderRequiresGC(hi)) {
+ // App doesn't want GC but library requires it - bad
+ _objc_inform_now_and_on_crash
+ ("'%s' was compiled with -fobjc-gc-only, "
+ "but the application does not support GC",
+ _nameForHeader(hi->mhdr));
+ busted = YES;
+ }
+
+ if (PrintGC) {
+ _objc_inform("GC: library '%s' %s",
+ _nameForHeader(hi->mhdr), _gcForHInfo(hi));
+ }
+ }
+
+ if (busted) {
+ // GC state is not consistent.
+ // Kill the process unless one of the forcing flags is set.
+ if (!DisableGC) {
+ _objc_fatal("*** GC capability of application and some libraries did not match");
+ }
+ }
+}
+
+
+/***********************************************************************
+* gc_enforcer
+* Make sure that images about to be loaded by dyld are GC-acceptable.
+* Images linked to the executable are always permitted; they are
+* enforced inside map_images() itself.
+**********************************************************************/
+static BOOL InitialDyldRegistration = NO;
+static const char *gc_enforcer(enum dyld_image_states state,
+ uint32_t infoCount,
+ const struct dyld_image_info info[])
+{
+ uint32_t i;
+
+ // Linked images get a free pass
+ if (InitialDyldRegistration) return NULL;
+
+ if (PrintImages) {
+ _objc_inform("IMAGES: checking %d images for compatibility...",
+ infoCount);
+ }
+
+ for (i = 0; i < infoCount; i++) {
+ const headerType *mhdr = (const headerType *)info[i].imageLoadAddress;
+ if (bad_magic(mhdr)) continue;
+
+ objc_image_info *image_info;
+ size_t size;
+
+ if (mhdr == &_mh_dylib_header) {
+ // libobjc itself - OK
+ continue;
+ }
+
+#if !__OBJC2__
+ // 32-bit: __OBJC seg but no image_info means no GC support
+ if (!getsegbynamefromheader(mhdr, SEG_OBJC)) {
+ // not objc - assume OK
+ continue;
+ }
+ image_info = _getObjcImageInfo(mhdr, _getImageSlide(mhdr), &size);
+ if (!image_info) {
+ // No image_info - assume GC unsupported
+ if (!UseGC) {
+ // GC is OFF - ok
+ continue;
+ } else {
+ // GC is ON - bad
+ if (PrintImages || PrintGC) {
+ _objc_inform("IMAGES: rejecting %d images because %s doesn't support GC (no image_info)", infoCount, info[i].imageFilePath);
+ }
+ return "GC capability mismatch";
+ }
+ }
+#else
+ // 64-bit: no image_info means no objc at all
+ image_info = _getObjcImageInfo(mhdr, _getImageSlide(mhdr), &size);
+ if (!image_info) {
+ // not objc - assume OK
+ continue;
+ }
+#endif
+
+ if (UseGC && !_objcInfoSupportsGC(image_info)) {
+ // GC is ON, but image does not support GC
+ if (PrintImages || PrintGC) {
+ _objc_inform("IMAGES: rejecting %d images because %s doesn't support GC", infoCount, info[i].imageFilePath);
+ }
+ return "GC capability mismatch";
+ }
+ if (!UseGC && _objcInfoRequiresGC(image_info)) {
+ // GC is OFF, but image requires GC
+ if (PrintImages || PrintGC) {
+ _objc_inform("IMAGES: rejecting %d images because %s requires GC", infoCount, info[i].imageFilePath);
+ }
+ return "GC capability mismatch";
+ }
+ }
+
+ return NULL;
+}
+
+// !defined(NO_GC)
+#endif
+
+
+/***********************************************************************
+* map_images_nolock
+* Process the given images which are being mapped in by dyld.
+* All class registration and fixups are performed (or deferred pending
+* discovery of missing superclasses etc), and +load methods are called.
+*
+* info[] is in bottom-up order i.e. libobjc will be earlier in the
+* array than any library that links to libobjc.
+*
+* Locking: loadMethodLock(old) or runtimeLock(new) acquired by map_images.
+**********************************************************************/
+__private_extern__ const char *
+map_images_nolock(enum dyld_image_states state, uint32_t infoCount,
+ const struct dyld_image_info infoList[])
+{
+ static BOOL firstTime = YES;
+ static BOOL wantsGC NOBSS = NO;
+ uint32_t i;
+ header_info *hi;
+ header_info *hList[infoCount];
+ uint32_t hCount;
+
+ // Perform first-time initialization if necessary.
+ // This function is called before ordinary library initializers.
+ // fixme defer initialization until an objc-using image is found?
+ if (firstTime) {
+#ifndef NO_GC
+ InitialDyldRegistration = YES;
+ dyld_register_image_state_change_handler(dyld_image_state_mapped, 0 /* batch */, &gc_enforcer);
+ InitialDyldRegistration = NO;
+#endif
+ }
+
+ if (PrintImages) {
+ _objc_inform("IMAGES: processing %u newly-mapped images...\n", infoCount);
+ }
+
+
+ // Find all images with Objective-C metadata.
+ hCount = 0;
+ i = infoCount;
+ while (i--) {
+ const headerType *mhdr = (headerType *)infoList[i].imageLoadAddress;
+
+ hi = _objc_addHeader(mhdr);
+ if (!hi) {
+ // no objc data in this entry
+ continue;
+ }
+
+ hList[hCount++] = hi;
+
+
+ if (PrintImages) {
+ _objc_inform("IMAGES: loading image for %s%s%s%s%s\n",
+ _nameForHeader(mhdr),
+ mhdr->filetype == MH_BUNDLE ? " (bundle)" : "",
+ _objcHeaderIsReplacement(hi) ? " (replacement)" : "",
+ _objcHeaderOptimizedByDyld(hi)?" (preoptimized)" : "",
+ _gcForHInfo2(hi));
+ }
+ }
+
+ // Perform one-time runtime initialization that must be deferred until
+ // the executable itself is found. This needs to be done before
+ // further initialization.
+ // (The executable may not be present in this infoList if the
+ // executable does not contain Objective-C code but Objective-C
+ // is dynamically loaded later. In that case, check_wants_gc()
+ // will do the right thing.)
+#ifndef NO_GC
+ if (firstTime) {
+ wantsGC = check_wants_gc();
+
+ verify_gc_readiness(wantsGC, hList, hCount);
+
+ gc_init(wantsGC); // needs executable for GC decision
+ rtp_init(); // needs GC decision first
+ } else {
+ verify_gc_readiness(wantsGC, hList, hCount);
+ }
+
+ if (wantsGC) {
+ // tell the collector about the data segment ranges.
+ for (i = 0; i < hCount; ++i) {
+ hi = hList[i];
+ const segmentType *dataSegment = hi->os.dataSegmentHeader;
+ const segmentType *objcSegment = hi->os.objcSegmentHeader;
+ if (dataSegment) {
+ gc_register_datasegment(dataSegment->vmaddr + hi->os.image_slide, dataSegment->vmsize);
+ }
+ if (objcSegment) {
+ // __OBJC contains no GC data, but pointers to it are
+ // used as associated reference values (rdar://6953570)
+ gc_register_datasegment(objcSegment->vmaddr + hi->os.image_slide, objcSegment->vmsize);
+ }
+ }
+ }
+#endif
+
+ if (firstTime) {
+ extern SEL FwdSel; // in objc-msg-*.s
+ sel_init(wantsGC);
+ FwdSel = sel_registerName("forward::");
+ }
+
+ _read_images(hList, hCount);
+
+ firstTime = NO;
+
+ return NULL;
+}
+
+
+/***********************************************************************
+* load_images_nolock
+* Prepares +load in the given images which are being mapped in by dyld.
+* Returns YES if there are now +load methods to be called by call_load_methods.
+*
+* Locking: loadMethodLock(both) and runtimeLock(new) acquired by load_images
+**********************************************************************/
+__private_extern__ BOOL
+load_images_nolock(enum dyld_image_states state,uint32_t infoCount,
+ const struct dyld_image_info infoList[])
+{
+ BOOL found = NO;
+ uint32_t i;
+
+ i = infoCount;
+ while (i--) {
+ header_info *hi;
+ for (hi = FirstHeader; hi != NULL; hi = hi->next) {
+ const headerType *mhdr = (headerType*)infoList[i].imageLoadAddress;
+ if (hi->mhdr == mhdr) {
+ prepare_load_methods(hi);
+ found = YES;
+ }
+ }
+ }
+
+ return found;
+}
+
+
+/***********************************************************************
+* unmap_image_nolock
+* Process the given image which is about to be unmapped by dyld.
+* mh is mach_header instead of headerType because that's what
+* dyld_priv.h says even for 64-bit.
+*
+* Locking: loadMethodLock(both) and runtimeLock(new) acquired by unmap_image.
+**********************************************************************/
+__private_extern__ void
+unmap_image_nolock(const struct mach_header *mh, intptr_t vmaddr_slide)
+{
+ if (PrintImages) {
+ _objc_inform("IMAGES: processing 1 newly-unmapped image...\n");
+ }
+
+ header_info *hi;
+
+ // Find the runtime's header_info struct for the image
+ for (hi = FirstHeader; hi != NULL; hi = hi->next) {
+ if (hi->mhdr == (const headerType *)mh) {
+ break;
+ }
+ }
+
+ if (!hi) return;
+
+ if (PrintImages) {
+ _objc_inform("IMAGES: unloading image for %s%s%s%s\n",
+ _nameForHeader(hi->mhdr),
+ hi->mhdr->filetype == MH_BUNDLE ? " (bundle)" : "",
+ _objcHeaderIsReplacement(hi) ? " (replacement)" : "",
+ _gcForHInfo2(hi));
+ }
+
+#ifndef NO_GC
+ if (UseGC) {
+ const segmentType *dataSegment = hi->os.dataSegmentHeader;
+ const segmentType *objcSegment = hi->os.objcSegmentHeader;
+ if (dataSegment) {
+ gc_unregister_datasegment(dataSegment->vmaddr + hi->os.image_slide, dataSegment->vmsize);
+ }
+ if (objcSegment) {
+ gc_unregister_datasegment(objcSegment->vmaddr + hi->os.image_slide, objcSegment->vmsize);
+ }
+ }
+#endif
+
+ _unload_image(hi);
+
+ // Remove header_info from header list
+ _objc_removeHeader(hi);
+ _free_internal(hi);
+}
+
+
+/***********************************************************************
+* _objc_init
+* Static initializer. Registers our image notifier with dyld.
+**********************************************************************/
+static __attribute__((constructor))
+void _objc_init(void)
+{
+ // fixme defer initialization until an objc-using image is found?
+ environ_init();
+ tls_init();
+ lock_init();
+ exception_init();
+
+ // Register for unmap first, in case some +load unmaps something
+ _dyld_register_func_for_remove_image(&unmap_image);
+ dyld_register_image_state_change_handler(dyld_image_state_bound,
+ 1/*batch*/, &map_images);
+ dyld_register_image_state_change_handler(dyld_image_state_dependents_initialized, 0/*not batch*/, &load_images);
+}
+
+
+/***********************************************************************
+* _headerForAddress.
+* addr can be a class or a category
+**********************************************************************/
+static const header_info *_headerForAddress(void *addr)
+{
+ unsigned long size;
+ unsigned long seg;
+ header_info * hi;
+
+ // Check all headers in the vector
+ for (hi = FirstHeader; hi != NULL; hi = hi->next)
+ {
+ // Locate header data, if any
+ const segmentType *segHeader;
+#if __OBJC2__
+ segHeader = hi->os.dataSegmentHeader;
+#else
+ segHeader = hi->os.objcSegmentHeader;
+#endif
+ if (!segHeader) continue;
+ seg = segHeader->vmaddr + hi->os.image_slide;
+ size = segHeader->filesize;
+
+ // Is the class in this header?
+ if ((seg <= (unsigned long) addr) &&
+ ((unsigned long) addr < (seg + size)))
+ return hi;
+ }
+
+ // Not found
+ return 0;
+}
+
+
+/***********************************************************************
+* _headerForClass
+* Return the image header containing this class, or NULL.
+* Returns NULL on runtime-constructed classes, and the NSCF classes.
+**********************************************************************/
+__private_extern__ const header_info *_headerForClass(Class cls)
+{
+ return _headerForAddress(cls);
+}
+
+
+/**********************************************************************
+* secure_open
+* Securely open a file from a world-writable directory (like /tmp)
+* If the file does not exist, it will be atomically created with mode 0600
+* If the file exists, it must be, and remain after opening:
+* 1. a regular file (in particular, not a symlink)
+* 2. owned by euid
+* 3. permissions 0600
+* 4. link count == 1
+* Returns a file descriptor or -1. Errno may or may not be set on error.
+**********************************************************************/
+__private_extern__ int secure_open(const char *filename, int flags, uid_t euid)
+{
+ struct stat fs, ls;
+ int fd = -1;
+ BOOL truncate = NO;
+ BOOL create = NO;
+
+ if (flags & O_TRUNC) {
+ // Don't truncate the file until after it is open and verified.
+ truncate = YES;
+ flags &= ~O_TRUNC;
+ }
+ if (flags & O_CREAT) {
+ // Don't create except when we're ready for it
+ create = YES;
+ flags &= ~O_CREAT;
+ flags &= ~O_EXCL;
+ }
+
+ if (lstat(filename, &ls) < 0) {
+ if (errno == ENOENT && create) {
+ // No such file - create it
+ fd = open(filename, flags | O_CREAT | O_EXCL, 0600);
+ if (fd >= 0) {
+ // File was created successfully.
+ // New file does not need to be truncated.
+ return fd;
+ } else {
+ // File creation failed.
+ return -1;
+ }
+ } else {
+ // lstat failed, or user doesn't want to create the file
+ return -1;
+ }
+ } else {
+ // lstat succeeded - verify attributes and open
+ if (S_ISREG(ls.st_mode) && // regular file?
+ ls.st_nlink == 1 && // link count == 1?
+ ls.st_uid == euid && // owned by euid?
+ (ls.st_mode & ALLPERMS) == (S_IRUSR | S_IWUSR)) // mode 0600?
+ {
+ // Attributes look ok - open it and check attributes again
+ fd = open(filename, flags, 0000);
+ if (fd >= 0) {
+ // File is open - double-check attributes
+ if (0 == fstat(fd, &fs) &&
+ fs.st_nlink == ls.st_nlink && // link count == 1?
+ fs.st_uid == ls.st_uid && // owned by euid?
+ fs.st_mode == ls.st_mode && // regular file, 0600?
+ fs.st_ino == ls.st_ino && // same inode as before?
+ fs.st_dev == ls.st_dev) // same device as before?
+ {
+ // File is open and OK
+ if (truncate) ftruncate(fd, 0);
+ return fd;
+ } else {
+ // Opened file looks funny - close it
+ close(fd);
+ return -1;
+ }
+ } else {
+ // File didn't open
+ return -1;
+ }
+ } else {
+ // Unopened file looks funny - don't open it
+ return -1;
+ }
+ }
+}
+
+
+/***********************************************************************
+* _objc_internal_zone.
+* Malloc zone for internal runtime data.
+* By default this is the default malloc zone, but a dedicated zone is
+* used if environment variable OBJC_USE_INTERNAL_ZONE is set.
+**********************************************************************/
+__private_extern__ malloc_zone_t *_objc_internal_zone(void)
+{
+ static malloc_zone_t *z = (malloc_zone_t *)-1;
+ if (z == (malloc_zone_t *)-1) {
+ if (UseInternalZone) {
+ z = malloc_create_zone(vm_page_size, 0);
+ malloc_set_zone_name(z, "ObjC");
+ } else {
+ z = malloc_default_zone();
+ }
+ }
+ return z;
+}
+
+
+// TARGET_OS_MAC
+#else
+
+
+#error unknown OS
+
+
+#endif
projects / apple / objc4.git / blobdiff